Aluminium oxide is impermeable and, unlike the oxide layers on many other metals, it adheres strongly to the parent metal. If damaged mechanically, aluminiumâs oxide layer repairs itself immediately.
Saliva helps remove oral waste and cavity-causing bacteria, protects teeth from decay by neutralizing harmful acids, and helps re-mineralize tooth enamel. Saliva also keeps oral tissues healthy by preventing infection by controlling bacteria and fungi in the mouth.
In order to help with a diagnosis, it is important to identify if the bleeding is only evident in the saliva during or after one or more of the following 1  : Eating or drinking. 2  Biting, chewing or swallowing. 3  Brushing, gargling with a mouth rinse or flossing. 4  Talking or shouting. 5  Breathing through the mouth.